package danli;


public class SingleModel {
    private static SingleModel singleModel;

    private SingleModel() {
    }

    public static SingleModel getInstance() {
        if (singleModel == null) {
            synchronized (SingleModel.class) {
                if (singleModel == null) {
                    singleModel = new SingleModel();
                }
            }

        }
        return singleModel;
    }
}

